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JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
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We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
A receipt should have been emailed to your account email from what I know.
However, if that doesn't happen just know that you can safely obtain one from within your Account >>> Billing >>> Invoices.
You can refer to this guide here https://www.jotform.com/help/329-How-to-check-invoices.